Display screen or portion thereof with transitional graphical user interface



FIG. 1 is a front view of a first embodiment of a display screen orportion thereof with transitional graphical user interface showing afirst image in a sequence, showing our new design;

FIG. 2 is a front view showing a second image thereof;

FIG. 3 is a front view showing a third image thereof;

FIG. 4 is a front view showing a fourth image thereof;

FIG. 5 is a front view of a second embodiment of a display screen orportion thereof with transitional graphical user interface showing afirst image in a sequence;

FIG. 6 is a front view showing a second image thereof;

FIG. 7 is a front view showing a third image thereof;

FIG. 8 is a front view showing a fourth image thereof;

FIG. 9 is a front view showing a fifth image thereof; and,

FIG. 10 is a front view showing a sixth image thereof.

The outermost broken lines illustrating portions of a display screenform no part of the claimed design. The remainder of the broken linesdepict portions of the graphical user interface that form no part of theclaimed design.

The appearance of the transitional image sequentially transitionsbetween the images shown in FIGS. 1-4 and 5-10. The process or period inwhich one image transitions to another image forms no part of theclaimed design.

CLAIM The ornamental design for a display screen or portion thereof withtransitional graphical user interface, as shown and described.